Material comminutors



June 28, 1966 M. H. PANNING 3,258,210

MATERIAL COMMINUTORS Filed Sept. 7, 1965 5 Sheets-Sheet 1 0 II I, 0 X7,

m M lllw" O INVENTOR.

June 28, 1966 M. H. PANNING MATERIAL COMMINUTORS 5 Sheets-Sheet 2 FiledSept. 7, 1965 INVENTOR. #029! of 72/11/07,.-

June 28, 1966 M. H. PANNING MATERIAL COMMINUTORS 5 Sheets-Sheet 5 FiledSept. 7, 1965 av mm m a m? w# M H M June 28, 1966 M. H. PANNING3,258,210

MATERIAL COMMINUTORS Filed Sept. 7, 1965 5 Sheets-Sheet 4 l a; l "M-4.1% mm mm mm mm IM HIM-NU June 28, 19

M. H. PANNING MATERIAL COMMINUTORS 5 Sheets-Sheet 5 United States Patent3,258,210 MATERIAL COMMINUTORS Martin H. Panning, 304 Sunny Lane,Thiensville, Wis. Filed Sept. 7, 1965, Ser. No. 489,794 27 Claims. (Cl.24185) The present invention is directed to new and useful improvementsin comminuting machines, including machines which will shred or tearmaterial, and machines which more or less grind or pulverize material.Machines of the type disclosed herein have particular usefulness inconnection with the comminuting of paper boxes, bailed material, woodpellets, and some metal materials.

This application is a continuation in part of my copending applicationSerial No. 292,694, filed July 3, 1963.

The major purposes of the present invention are to so form comminutingmachines that the comminuting space within the machine can be maintainedsubstantially full of material to be comminuted, while at the same timeforming such machines as to avoid overloading the drive or thecomminuting elements of the machine, and avoiding any kicking actionwhich would tend to throw material back out of the feed opening of themachine, the system being so arranged that upon jamming of materialbetween the comminuting elements, the comminuting elements of themachine tend, automatically, to dislodge such jammed material withoutcausing undue loads on the drive mechanism of the machine, the entireassembly being so formed as to enable use of relatively simple drivemechanism for the comminuting elements and relatively simple andinexpensive ripping, tearing or com minuting elements for the machine.

A related purpose of the invention is to so arrange a comminutingmachine that shredding elements used in the machine may be operated inreverse directions with respect to one another, thereby adding life tothe shredding elements.

Another related purpose of the invention is to create new and usefulimprovements in arrangements of comminuting teeth for a comminutingmachine.

These and other purposes of the invention will become more apparent inthe course of the ensuing specification and claims, when taken with theaccompanying drawings, in which:

FIGURE 1 is an end view of a typical comminuting machine embodying theprinciples of the present invention and particularly illustrating theinlet end of the comminuting machine;

FIGURE 2 is a plan view of the machine illustrated in FIGURE 1;

FIGURE 3 is a side view of a comminuting machine of the type illustratedin FIGURES 1 and 2, but arranged at an inclination to the horizontal;

FIGURE 4 is a sectional view of the comminuting machine illustrated inFIGURE 1 and taken on the section lines 44 of FIGURE 1; and

FIGURE 5 is an end view of a portion of the comminuting machineillustrated in FIGURE 1 while illustrating another operative position ofthe elements shown in FIGURE 1;

FIGURE 6 is a side view, in section, of a further embodiment of theinvention;

FIGURE 7 is a sectional illustration of a portion of the modificationillustrated in FIGURE 6, and taken along the section lines 77 of FIGURE6;

FIGURE 8 is a top view of a ripping bar and arm assembly illustrated inFIGURE 6;

. FIGURE 9 is a plan view of one element illustrated in FIGURES 6, 7 and8;

FIGURE 10 is an end view of the element illustrated in FIGURE 9;

FIGURE 11 is an end view of a certain tooth structure usable with theinner wall of the drum illustrated in FIGURE 6;

FIGURE 12 is a plan view of the element illustrated in FIGURE 11; and

FIGURE 13 is a diagrammatic view, in section, of a modified form ofmachine using certain principles which may be applied to both of themachines in FIGURES 1 through 12, inclusive.

With particular reference to the drawings, wherein like elements aredesignated by like characters throughout and in the first instance toFIGURE 1, the numeral 10 generally designates an elongated, generallycylindrically formed housing, which housing may be supported by asuitable frame means 11. The machine illustrated in FIGURES 1 through 5is one embodiment of the invention, which is particularly useful inshredding material as through a ripping and tearing action. Frame means11 may be supported on a floor or the like and may be so arranged as tosupport housing 10 with its axis generally horizontal as in FIGURES 1, 4and 5 or at an angle to the horizontal as in FIGURE 3. An end plate 12is bolted to one end of the housing 10 and has a relatively largeopening 13 formed therein, which opening 13 provides an inlet opening tothe interior of the housing and to certain shredding elements which willbe described hereinafter. A drive means for the machine is carried bythe frame means 11 and as seen in the drawings may consist of anelectric motor 14 which drives a gear reducer 15, which in turn has anoutput shaft 16 adapted for an operative connection with the shreddingelements.

In accordance with the principles of the invention, a generallycylindrical drum 17 is mounted within housing 10, but with the wall ofthe drum .in spaced relation to the wall of the housing, as appears bestin FIGURE 4. One end of drum 17, as for example, the end adjacent theinlet opening 13 is open, whereas the opposite end of drum 17 is closedby an end wall 18, which is positioned closely adjacent to an end wall19 for the housing-10. The inlet end of the drum is supported forrotation in housing 10 by means of a bearing wheel which may consist ofa plurality of rollers 20 spaced about the circumference of the drum andin bearing engagement therewith and supported by the housing 10 and/ orframe means 11. The enclosed end of the drum is supported on and fixedto a shaft 21, which is supported on the end walli19 of housing 10 andsupported for rotation and a bearing 22, which bearing is supported bythe frame means 11. Drum 17 is adapted to be rotated about itslongitudinal axis, which is coaxial with the axis of the cylindricalportion of the drum and with shaft 21, by means of a roller chain driveas provided by a sprocket 23 driven by shaft 16, a sprocket 24 which isfixed to shaft 21 and a chain in the form of a roller chain, which isdiagrammatically indicated at25 in FIGURE 2.

The interior wall of the drum has a plurality of shredding teeth fixedthereto and projecting inwardly with respect thereto. These teeth 26 arearranged in longitudinally spaced rows, as appears best in FIGURE 4 andare so arranged that they define a spiral pattern wound about thelongitudinal axis of the drum. These teeth are gen erally triangular incross section taken longitudinally of the drum and may be generallyrectangular in cross sec tion taken transversely of the drum. The pointsthereof extend radially toward the axis of the drum. v

A ripper bar 27 is mounted for rotation within the drum. Bar 27 isadapted to rotate about the longitudinal axis of the drum and withrelation to the drum. This ripper bar is relatively heavy and issupported at one end thereof by means of an arm 28, which is freelysupported for rotation on the inwardly projecting end of drive shaft 21.The other end of the ripper bar 27 has a ring 29 fixed thereto, whichring 29 serves as a bearing ring for a cooperable supporting and bearingengagement with the inner wall of the drum at the inlet end thereof.Ring 29 may be so formed as to provide a plurality of peripherallyspaced roller bearings for engagement wtih the inner wall of the drum atthe inlet end of the drum. Ripper bar 27 has a plurality oflongitudinally spaced receses 30 formed along the side or edge thereofclosest to the wall of the drum. These recesses are spaced in accordancewith the longitudinal spacing of the rows of teeth on the wall of thedrum and are shaped to complement the triangular shape of the teeth 26.Ripper bar 27 is so pos1 tioned that during rotation of the drum, one ormore teeth spaced longitudinally of the drum are within one or more ofthe openings 30 in the ripper bar. As the drum rotates, teeth movesuccessively into the openings in the ripper bar. The spacing of theteeth, as shown, is so arranged that a plurality of teeth are within theopenings in the ripper bar at any given time, but these teeth are spacedalong the length of the drum. Then as the drum rotates, additional anddifferent teeth move into the openings in the ripper bar 27, but atdifferent and longitudinally spaced recesses on the ripper bar.

Ripper bar 27 is formed to provide a relatively heavy mass for purposeswhich will appear hereinafter. It has a transverse cross-sectional area,as appears in FIGURES 1 and many times the area of a tooth.

The end portion of the drum 17 which is remote from the inlet end isprovided with a plurality of spaced openings 31, which openings may bepositioned between the teeth on the Wall of the drum. Openings 31provide egress of small pieces of shredded material through the wall ofthe drum and to a discharge space or opening 32 which is formed in thehousing in the rearward portion thereof. Material passing through theopenings may be guided to this opening by passing through the relativelysmall clearance space between the wall of the housing and the opposedwall of drum 17. This small clearance space tends to insure that onlysmall shredded pieces are discharged, in that elongated pieces ofmaterial may have a width such that an end portion thereof may pass outthrough the openings until contact with the housing wall which tends tokeep the remainder of such pieces within the drum for a furthershredding action.

With particular reference now to FIGURES 6 through 12, inclusive, afurther embodiment of the invention is illustrated.

In FIGURE 6, for example, a housing 40 may take the same general form asthe form of the housing 10 in FIG- URES 1 through 5, inclusive. Housing40 may be supported by suitable frame means 41. A material comminutingdrum 42 is supported within the housing for rotation about an axisextending generally longitudinally of the housing and inclined to thehorizontal as illustrated in FIGURE 6. Drum 42 has an inlet opening 43formed in one outer end 44, which is the higher end. This inlet end 44of the drum may be supported for rotation on hearing means 45 at theinlet end thereof, which bearing means are carried by the housing 40.The other, or lower end of drum 42 may be rotatably supported on a shaft46 which is positioned coaxially with the axis of rotation of the drum42. Drum 42 may be rotatably mounted on the shaft 46 by means ofsuitable sleeve bearings 47.

- Shaft 46 may be rotatably supported in cantilever fashion by a bearingpost 48 which is positioned exteriorly of the housing end drum. Thebearing post 48 may be carried by the supporting frame 41 for thehousing.

Drum 42 has a plurality of generally equally spaced openings formed inthe wall thereof, as at 49 in a fashion similar to the openings 31 inFIGURES 1 through 5. Openings 49 are spaced around the circumference ofthe drum and substantially from end to end of the drum. These openingsin drum 42 provide discharge outlets for material comminuted within thedrum. Material passing through these discharge openings may pass to thehousing,

where they may be removed or stored in accordance with the desired useof the comminuted material.

Drive means for the drum 42 are provided by means of a motor and driveassembly (not shown in FIGURES 6- 12) similar to that illustrated inFIGURES 1 through 5. A sprocket 50 is diagrammatically shown in FIGURE6, which sprocket 50 is fixed to the bearing sleeve 47 for the drum sothat upon rotation of the sprocket 50, the drum will rotate therewithand about the axis of the shaft 46. It should be understood that theillustration of the sprocket 59 is representative of a sprocket drive,gear drive, or other equivalent means for rotating the drum 42.

In order to comminute material within the drum, a ripper bar, orcomminuting bar, generally designated at 51, is carried at the inner endof shaft 46 and fixed thereto. The bar 51 may be supported on the innerend of shaft 46 as by means of a sleeve or collar 52 which is keyed toshaft 46 for rotation therewith, as appears in FIGURE '7. The bar 51 maybe supported by means of angle members 53 which are affixed to thesleeve 52 .and extended outwardly with respect to shaft 46. These anglemembers are fixed to a plate 54. Plate 54 has a tooth assembly generallydesignated at 55, removably connected to the outer surface of plate 54as by means of bolts or screws 56. The tooth assembly further includes apair of elongated plates 57 and 58 which are adapted to extend generallyparallel to the axis of shaft 46. These plates 57 and 58 may be fixed toan upper plate 59 which is bolted to the plate 54. Transverse plates 60are welded or otherwise fixed to the plates 57, 58 and 59 An elongatedcurvilinear plate 61 spans the space between the outer extremities ofthe plates 57 and 58 and may be fixed to these plates as well as plate6% by means of welding or the like. The curvature of plate 61 generallymatches the curvature of the drum.

Elongated tooth bars 62 are fixed to the exposed surfaces of plates 57and 58 as appears in FIGURE 7. These tooth bars are formed with teeth 63along the marginal edges thereof at both sides and at both ends thereofas appears in FIGURE 9. These tooth bars 62 have elongated slots 64 atspaced intervals along their length so that securing bolts 65 may bepassed through the slots and into apertures in the plates 57 and 58 soas to hold the tooth bars 62 in the general relation illustrated inFIGURE 7.

These tooth bars are so positioned that they extend radially outwardlybeyond the lower plate 61 and the lower edges of the plates 57 and 58 asappears in FIG- URE 7, while providing a clearance with the inner wallof the drum. This clearance space may be adjusted through adjustment ofthe tooth bars 62 radially inwardly and outwardly with respect to theaxis of the supporting shaft 46 by means of the adjustment slots 64. Byhaving teeth on both marginal side edges of the tooth bars, the toothbars may be reversed after one side has become worn, thereby presentinga new and sharp set of teeth for the comminuting action.

In order to provide tooth means on the inner surface of the drum for acooperable comminuting action with the teeth 63 of the ripper arm, aseries of removable plates 66 are provided. These plates may be formedof ductile iron or the like and may be cast in the general figurationillustrated in FIGURE 12 with spaced teeth 67 on the inner surfacethereof. These plates, as appears in FIGURE 11, are curvilinear in formso as to match the curvature of the inner wall of the drum. These toothplates 66 may be fixed to the inner wall of the drum 42 as by means ofbolts or the like which are passed through apertures 68 in the toothplates. These tooth plates are so proportioned that when fixed to theinner wall of the drum 42, a slight clearance space still exists betweenthe teeth 63 of the teeth on the arm and the teeth 67 of the drum, asthese teeth pass one another.

The exterior end of the ripper arm supporting shaft 46 may carry asprocket, gear or pulley, as diagrammatically represented at 69. Springmeans, or the like may be interconnected with this sprocket or gear soas to bias the arm 55 toward the position illustrated in the drawings.

Suitable conveying or feed means, as is diagrammatically indicated in 33in FIGURE 1, may be used to supply the material to be comminuted to andthrough the inlet opening for the drum in either form of the invention.Also suitable means, not shown, may be provided to convey comminutedmaterial passed through the discharge openings 32, or discharge openings49.

FIGURE 13 illustrates certain principles which may be utilized in eitherform of machine illustrated in FIG- URES 1 through 12, inclusive. InFIGURE 13 the drum is diagrammatically represented at 7B and a ripperbar is diagrammatically represented at 71. The interior wall of the drummay carry tooth means, diagrammatically represented at 72, and which maybe considered representative of either form of drum tooth meansillustrated in FIGURES 1 through 12, inclusive. The ripper'bar 71 mayhave a series of openings to co-operate with the tooth means 72, as inFIGURES 1 through 5, or it may carry co-operating teeth as isillustrated in FIGURES 6 through 12, inclusive.

In FIGURE 13, the end of the drum remote from the inlet end is supportedon a stationary supporting shaft 73 as by means of bearings 74 carriedby the end wall 75 of the drum and positioned for bearing engagementwith the supporting shaft 73. Supporting shaft 73 is supported incantilever fashion by a bearing post 730. A sprocket 76 is fixed to abearing housing 77 for the bearings 74. Suitable drive means, as, forexample, a motor and chain may be used to drive sprocket 76 and thusrotate the drum about its longitudinal axis generally designated at 78.

In FIGURE 13 the ripper bar is carried by a supporting shaft 79 which isrotatably supported in the fixed shaft 73 as by means of bearings 80 and81. The shaft 79 for the ripper bar is passed through a bore in thesupporting shaft 73 and is mounted for rotation about an axis eccentricto the axis 78 of the drum. This eccentric axis is designated at 82.

It is preferred to oifset axis 82 toward the lowermost part of the drum.The outer end of shaft 79 may carry a crank 83 with which spring ordashpot facilities may be employed to resist rotation of the ripper bar71.

By offsetting the axis of rotation of the ripper bar 71, a variableclearance space exists between the ripper bar and the interior wall ofthe drum. This space is smallest when the ripper bar is in its normaloperating position in the lower part of the drum. When material beingcomminuted is jammed between the ripper bar and the lower part of thedrum which causes the ripper bar to rotate with the drum, the clearancespace between the ripper bar and the interior wall of the drumprogressively increases to a point of maximum clearance at or near thetop of the drum. This progressively increasing clearance produced by theotfset positioning of the ripper bar will tend to quickly clear thejammed material between the ripper bar and the drum so that the bar mayreturn to its lower operative position.

In the operation of all forms of the invention, material to becomminuted, such as paper, cardboard, baled boxes, pallets or othermaterial, is supplied through the inlet openings to the drums. As thismaterial is fed into the drum, some preliminary and relatively slighttearing, scoring, or comminuting action, may be imparted by the actionof the teeth at the inlet end of the drum. As the drum is rotated by thedrive means, material is tumbled within the drum and eventually passesbetween the ripper bar and the co-operable teeth carried by the drum.Material may pile up along the side of the ripper bar, in which eventthe lowermost layer of material, even though not passing between thedrum and the ripper bar, is comminuted by the continued scouring,abrading or tearing action of the teeth on the same. Material which doespass between the ripper bar and teeth on the drum is comminuted by theco-operative action of the bar and teeth. This comminuting actioncontinues until the material is reduced to pieces of such size that theymay pass out through the discharge openings in the wall of the drum andto the discharge space.

The ripper oar, due to its relatively heavy mass, tends to remain in thebottom portion of the drum so that some of the material within the drumconstantly passes between the bar and the opposed teeth on the drum.Material passing between the drum and the ripping bar is recirculatedaround the drum for another eventual pas sage therebetween. The teeth onthe drums tend to grip material so as to 'force it into the spacebetween the bar and drum.

In the form of the invention illustrated in FIGURES 1 through 5, theco-operative comminuting action of the teeth on the drum and thetooth-like openings in the ripper bar cause a positive shredding andtearing of material. The teeth 26 of the drum engage or grip thematerial in contact therewith so as to forceably m-ove such material toopenings in the bar 27.

In the form of the invention illustrated in FIGURES 6 through 12, theslight spacing between the ripper bar teeth and the teeth on the drum,creates more of a grinding action for grinding paper and similarproducts down to a fine mesh size. Some shredding of material does occurin the form of the invention illustrated in FIGURES 6 through 12, butthe closely spaced relation of the co-operable drum and bar teeth maygrind material down to a fine mesh size before it passes through thedischarge openings of the drum.

In some cases, material may be jammed between the ripper bar and theopposed teeth on the drum. In this event, the ripper bar, in both formsof the invention, will tend to rotate with the drum until the weight ofthe bar, and/or a biasing means for the bar, causes the bar to workitself free. For example, material jamming the bar may cause the bar tomove clock-wise upwardly as seen in FIGURE 5, and free itself before itreaches the top of the drum, in which case it may then movecounterclockwise in FIGURE 5 to the bot-tom of the drum and shred orcomminute the jammed material in the process. On the other hand, if thejamming action is suflicient to carry the ripper bar to the very top ofthe drum and beyond, the heavy mass of the bar, as it passes the top ofthe drum will tend to accelerate itself and swing freely and faster thanthe drum, thus moving out of engagement with the jammed material inwhich case the ripper bar smashes downwardly into material in the lowerportion of the drum. If the ripper arm does not free itself from thisjammed material, it still may undergo several or more revolutions withthe drum in a more -or less fixed relation, and in the process graduallytear or rip the jammed material sutficiently for the ripper bar to freeitself.

In the form of the invention illustrated in FIGURES 1 through 5, thespiral spacing of the teeth within the drum intends to insure that onlya few teeth are working on material with the ripper bar at any one time,thus tending to enhance a uniform load on the drive means. In the formof the invention illustrated in FIGURES 6 through 12, inclusive, thespacing of the bars 62 insures that relatively few teeth of the drum areco-operating with few teeth of the ripper arm at the same time. Materialpassing between the teeth of one bar 62 and the drum enters a largerclearance space between the tooth bars 62, where it may still be workedupon on one side thereof, by the teeth on the drum.

In FIGURES 6 through 12, adjustment of the ripper teeth on the ripperarm in a radial direction with respect to the axis of the shaft 46,allows selectivity of the size to which the material is to be reduced.

In all forms of the invention, replaceable screens may be used with thedischarge openings in the wall of the drum. T-hese replaceable screensmay be made of different mesh sizes so as to allow selectivity of thesize of particles discharged from the drum. These screens may be oflarge mesh size where large particles are desired, or may be of smallmesh sizes where small particles are to be produced by the comminutingaction of the machine.

The drum may be operated in either direction of rotation so as to allowa greater life for the ripping teeth and ripping bar.

In either case, the drum may be maintained substantially full ofmaterial which is under a constant state of tumbling and agitation. Themachine may be operated at relatively slow speeds, for example, 10 to-50 revolutions per minute.

In order to assure that the resistance of the ripper bar to rotation isat a proper amount, it should be made relatively heavy. In addition, theeffective weight of the ripper bar 27 in FIGURES 1 through 5 may beincreased by fixing the ripper bar arm 28 to a shaft which is passedthrough the drive shaft 21 and with a crank arranged exteriorly of thehousing. A dash-pot arrangement may be connected to the crank to addresistance to rotational movement of the ripper bar. Springs can also beconnected to the crank for this purpose. Also, air check or hydrauliccheck devices may be connected to such a crank to augment the naturalresistance of the ripper bar to rotation.

The same result can be achieved in FIGURES 6 through 12, inclusive, byconnecting springs, air checks, or dash-pot devices to the gear orsprocket 69 which is afiixed to the ripper bar supporting shaft 46, asillustrated in FIGURE 6.

Such added resistance is especially desirable when the machine is usedfor comrninuting relatively heavy material.

The eccentric mounting of the ripper bar, as illustrated in FIGURE 13,may be employed with either form of the invention illustrated in FIGURES1 through 12, inclusive, so as to provide a progressively increasingclearance space as the ripper bar rotates with jammed material in thedrum to thereby free the material from the ripper bar and allow theripper bar to return to its position in the lowermost part of the drum.

Whereas I have shown an operative form of the invention, it should beunderstood that this showing and description thereof should be taken inan illustrative or diagrammatic sense only. There are many modificationsin and to the invention which will fall within the sco e and spiritthereof and which will be apparent to those skilled in the art. Thescope of the invention should be limited only by the scope of thehereinafter appended claims.

I claim:

1. A material shredder for corrugated board, cardboard and the likeincluding a drum mounted on a support for rotation and means forrotating the drum, said drum having an inlet opening in one end portionthereof and outlet means in the other end portion thereof, said drumhaving a plurality of spaced ripping teeth fixed to the interior wallthereof, and a ripping bar supported within said dru-m at a fixed,spaced relation to said interior wall, said bar having one edgepositioned adjacent the interior wall of said drum, said one edge havingspaced openings therein corresponding to the spacing of said teeth, saidripper bar being mounted to allow relative rotation of said drum withrespect to said bar to thereby cause a forced feeding of materialbetween said teeth and said bar and a shredding of the same.

2. The structure of claim 1 wherein said drum is mounted for rotationabout an axis inclined to a horizontal plane.

3. The structure of claim 1 wherein said teeth are arranged in a spiralpattern in the interior of the drum so as to cause successive passage ofsaid teeth into said spaced openings during rotation of said drumrelative to said bar.

4. The structure of claim 1 wherein said outlet means is S defined by aplurality of openings in the wall of said drum.

5. The structure of claim 1, characterized by and including a housingsurrounding said drum, said housing having a discharge openingpositioned to receive shredded material from said outlet means.

6. A material shredder for corrugated board, cardboard and the likeincluding a housing and a drum rotatably mounted within said housing,one end of said drum being closed and the other end being open, a driveshaft fixed to the closed end of said drum, supporting bearing means forsaid drive shaft, means for rotating said drive shaft to thereby rotatesaid drum about its longitudinal axis, outlet means in said drum,bearing means surrounding the open end of said drum and supported bysaid housing so as to support said open end, said drum having a rippingtooth fixed to the interior wall thereof, and a ripping bar supportedwithin said drum, said bar having one side positioned adjacent theinterior wall of said drum, said one side having an opening thereinpositioned to allow passage of said tooth therethrough during rotationof said drum, said ripper bar being mounted for rotation about said axisand to allow relative rotation of said drum with respect to said bar tothereby cause a forced feeding of material between said tooth and saidbar and a shredding of the same.

7. The structure of claim 6 wherein said drive shaft projects into theinterior of said drum and said ripper bar is rotatably supported on saiddrive shaft.

8. The structure of claim 6 wherein one end of said ripper bar issupported by a bearing ring in supporting and bearing engagement withthe wall of said drum.

9. The structure of claim 6 wherein said drum has a plurality oflongitudinally and peripherally spaced teeth, said ripper bar side has aplurality of spaced openings positioned to allow passage of said teeththerethrough, and said teeth are arranged in a spiral pattern in theinterior of the drum so as to cause successive passage of said teethinto said spaced openings during rotation of said drum relative to saidbar.

10. The structure of claim 6 wherein said outlet means is defined by aplurality of openings in the wall of said drum at a position remote fromsaid inlet end.

11. A material shredder for corrugated board, cardboard and the likeincluding a drum mounted on a support for rotation and means forrotating the drum about the longitudinal axis of said drum, said drumhaving an inlet opening in one end portion thereof and outlet meansspaced from said inlet opening, said drum having a ripping tooth fixedto the interior wall thereof, and a ripping bar supported within saiddrum, said bar having one side positioned closely adjacent the interiorwall of said drum, said one side having an opening therein positioned toallow passage of said tooth therethrough during rotation of said drum,said ripper bar being mounted for rotation about said axis while saidside is held in a fixed, spaced relation to said interior wall and toallow relative rotation of said drum with respect to said bar to therebycause -a forced feeding of material between said tooth and said bar anda shredding of the same.

12. The structure of claim 10 wherein a housing surrounds the peripheralwall of said drum and said outlet means is defined by a plurality ofspaced openings of smaller size than said inlet opening, said housinghas a discharge opening in the lower portion thereof and a wall portionoverlying said spaced openings but spaced a small distance therefrom sothat material passing through said openings will pass between said drumand said wall portion to said discharge opening.

13. A material comminutor including a drum mounted on a support forrotation and means for rotating the drum about the longitudinal axisthereof said drum having an inlet and outlet means therefor, said drumhaving ripping tooth means fixed to the interior wall thereof, a rippingbar supported within said drum, said bar being positioned adjacent theinterior wall of said drum, said bar having ripping tooth meansco-operable with the ripping tooth means on said wall, means mountingsaid ripper bar for rotation about said axis while holding said bar in afixed spaced relation to said interior wall and relative to said drum,to thereby cause a forced feeding of material between said interior walland said bar and a shredding of the same.

14. A material commiutor including a drum mounted on a support forrotation and means for rotating the drum about the longitudinal axisthereof, said drum having inlet and outlet means therefor, said drumhaving tooth means fixed to the interior wall thereof, a bar supportedwithin said drum, said bar being positioned adjacent the interior wallof said drum, said bar having comminuting means co-openable with thetooth means on said wall, means mounting said bar for rotation aboutsaid axis while holding said bar in a fixed spaced relation to saidinterior wall and relative to said drum, to thereby cause a forcedfeeding of material between said interior wall and said bar andcomminution of the same.

15. A material comminutor including a drum mounted on a support forrotation and means for rotating the drum about the longitudinal axisthereof, said drum having inlet and outlet means therefor, said drumhaving ripping tooth means fixed to the interior wall thereof, a rippingbar supported within said drum, said bar being positioned adjacent theinterior wall of said drum, said bar having comminuting meansco-operable with the ripping tooth means on said wall, means mountingsaid ripper bar for rotation about said axis while holding said bar in afixed spaced relation to said interior wall and relative to said drum,to thereby cause a forced feeding of material between said interior walland said bar and comminution of the same.

16. A material comminutor including a drum mounted on a support forrotation and means for rotating the drum about the longitudinal axisthereof, said drum having inlet and outlet means therefor, said drumhaving ripping tooth means fixed to the interior wall thereof, acomminuting bar supported within said drum and extending longitudinallythereof, said bar being positioned adjacent the interior wall of saiddrum, said bar having comminuting means 'co-operable with the toothmeans on said wall, means mounting said bar for rotation about said axiswhile holding said bar in a fixed spaced relation to said interior walland relative to said drum, to thereby cause a forced feeding of materialbetween said interior Wall and said bar and comminution of the same,said bar being normally positioned in a lower portion of said drum andbeing free to rotate about said axis in response to a predeterminedbuildup of material between said bar and the wall of said drum.

17. A material comminutor including a drum mounted on a support forrotation and means for rotating the drum about the longitudinal axisthereof, said drum having an inlet at the end thereof and outlet meanstherefor in the wall of the drum, said drum having ripping tooth meansfixed to the interior wall thereof, a comminuting bar supported withinsaid drum, said bar being positioned adjacent the interior wall of saiddrum, said bar having comminuting means co-operable with the tooth meanson said wall, means mounting said bar for rotation about said axis whileholding said bar in a fixed spaced relation to said interior wall andrelative to said drum, to thereby cause a forced feeding of materialbetween said interior wall and said bar and comminution of the same.

18. The structure of claim 17 wherein said bar is carried by a shaftextending through one end of said drum, said end of said drum beingrotatably supported on said shaft.

19. The structure of claim 17 wherein one end of said bar is rotatablysupported on the inlet end of said drum and the other end of said bar issupported on a shaft extending within the other end of said drum.

20. A material comminutor including a drum mounted on a support forrotation and means for rotating the drum about the longitudinal axisthereof, said drum having inlet and outlet means therefor, said drumhaving comminuting tooth means fixed to the interior wall thereof, a barsupported within said drum, said bar being positioned adjacent theinterior wall of said drum, said bar having comminuting tooth meansco-opera'ble with the tooth means on said wall, means mounting said barfor rotation about said axis while holding said bar in a fixed spacedrelation to said interior wall and relative to said drum, to therebycause a forced feeding of material between said interior wall and saidbar and comminution of the same.

21. The structure of claim 20 wherein a clearance exists between thetooth means on said wall and the tooth means on said bar.

22. The structure of claim 20 wherein the tooth means on said bar are ona plate removably mounted on said bar.

23. The structure of claim 20 wherein the tooth means on said wall arecarried by plates which are removably fixed to said wall.

24. A material comminutor including a drum mounted on a support forrotation and means for rotating the drum about the longitudinal axisthereof, said drum having inlet and outlet means therefor, said drumhaving tooth means fixed to the interior wall thereof, a bar supportedwithin said drum, said bar being positioned adjacent the interior wallof said drum, said bar being cooperable with the tooth means on saidwall for a comminution of material therebetween, and means mounting saidbar for movement in arcuate directions about the inner wall of said drumwhile maintaining a selected clearance between said bar and the interiorWall of said drum, to thereby cause a forced feeding of material betweensaid interior wall and said bar and comminution of the same.

25. The structure of claim 24 wherein said bar is mounted for movementabout said axis.

26. The structure of claim 24 wherein said bar is mounted for rotationalmovement about an axis parallel to said drum axis but offset toward thelower wall of said drum to thereby increase the clearance by a selectedamount as said bar rotates toward the top of said drum.

27. A material comminutor including a drum mounted on a support forrotation and means for rotating the drum about the longitudinal axisthereof, said drum having inlet and outlet means therefor, said drumhaving tooth means fixed to the interior wall thereof, a bar supportedwithin said drum, said bar being positioned adjacent the interior wallof said drum, said bar being co-operable with the tooth means on saidwall for a comminution of material therebetween, and means mounting saidbar for rotational movement within said drum while constraining said barto a selected spacing from the interior wall of said drum.

No references cited.

ROBERT C. RIORDON, Primary Examiner.

D. KELLY, Assistant Examiner.

17. A MATERIAL COMMINUTOR INCLUDING A DRUM MOUNTED ON A SUPPORT FORROTATION AND MEANS FOR ROTATING THE DRUM ABOUT THE LONGITUDINAL AXISTHEREOF, SAID DRUM HAVING AN INLET AT THE END THEREOF AND OUTLET MEANSTHEREFOR IN THE WALL OF THE DRUM, SAID DRUM HAVING RIPPING TOOTH MEANSFIXED TO THE INTERIOR WALL THEREOF, A COMMINUTING BAR SUPPORTED WITHINSAID DRUM, SAID BAR BEING POSITIONED ADJACENT THE INTERIOR WALL OF SAIDDRUM, SAID BAR HAVING COMMINUTING MEANS CO-OPERABLE WITH THE TOOTH MEANSON SAID WALL, MEANS MOUNTING SAID BAR FOR ROTATION ABOUT SAID AXIS WHILEHOLDING SAID BAR IN A FIXED SPACED RELATION TO SAID INTERIOR WALL ANDRELATIVE TO SAID DRUM, TO THEREBY CAUSE A FORCED FEEDING OF MATERIALBETWEEN SAID INTEIOR WALL AND SAID BAR AND COMMINUTION OF THE SAME.